Axial dystonia is a rare manifestation of adult onset primary segmental dystonia. Typically, patients present with cranio-cervical dystonia spreading to the trunk but not to the extremities. Affected patients are disabled predominantly by flexion spasms of the trunk which are worsened on action, especially during standing and walking.1 Response to drug therapy is often poor and local botulinum toxin injections are of limited value in these patients. Here we report a patient with primary axial dystonia who was successfully treated with bilateral deep brain stimulation (DBS) of the globus pallidus internus (GPi).

Case report

This 39-year-old woman presented with a 3 year history of truncal spasms with predominant flexion and lateral bending of the trunk. Onset was subacute over several weeks during her first pregnancy. There was gradual spread of dystonia from the trunk muscles to both shoulders and also to the neck, although axial dystonia remained predominant. Three years after disease onset, action induced dystonia was so severe that she was hardly able to walk because her trunk was flexed by almost 90° and also severely bent to the left side whenever she attempted to walk (see video segment 1 online). She also had right torticollis and left laterocollis. There was no dystonia in the arms or legs apart from mild writer’s cramp. Burke–Fahn–Marsden’s Dystonia Motor Score (BFMD) was 22.5. Past medical and family history was unremarkable. MRI of the brain and extensive laboratory investigations were …